/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   GtkRadiant is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#if !defined( INCLUDED_GTKUTIL_CURSOR_H )
#define INCLUDED_GTKUTIL_CURSOR_H

#include <glib.h>
#include <gdk/gdkevents.h>
#include <gtk/gtkwidget.h>
#include <gtk/gtkwindow.h>
#include <gtk/gtkmain.h>

#include "debugging/debugging.h"

typedef struct _GdkCursor GdkCursor;
typedef struct _GtkWidget GtkWidget;
typedef struct _GtkWindow GtkWindow;

#if 0
GdkCursor* create_blank_cursor();
void blank_cursor( GtkWidget* widget );
void default_cursor( GtkWidget* widget );
#endif
void Sys_GetCursorPos( GtkWindow* window, int *x, int *y );
void Sys_SetCursorPos( GtkWindow* window, int x, int y );



class DeferredMotion
{
guint m_handler;
typedef void ( *MotionFunction )( gdouble x, gdouble y, guint state, void* data );
MotionFunction m_function;
void* m_data;
gdouble m_x;
gdouble m_y;
guint m_state;

static gboolean deferred( DeferredMotion* self ){
	self->m_handler = 0;
	self->m_function( self->m_x, self->m_y, self->m_state, self->m_data );
	return FALSE;
}
public:
DeferredMotion( MotionFunction function, void* data ) : m_handler( 0 ), m_function( function ), m_data( data ){
}
void motion( gdouble x, gdouble y, guint state ){
	m_x = x;
	m_y = y;
	m_state = state;
	if ( m_handler == 0 ) {
		m_handler = g_idle_add( (GSourceFunc)deferred, this );
	}
}
static gboolean gtk_motion( GtkWidget *widget, GdkEventMotion *event, DeferredMotion* self ){
	self->motion( event->x, event->y, event->state );
	return FALSE;
}
};

class DeferredMotionDelta
{
int m_delta_x;
int m_delta_y;
unsigned int m_state;
guint m_motion_handler;
typedef void ( *MotionDeltaFunction )( int x, int y, unsigned int state, void* data );
MotionDeltaFunction m_function;
void* m_data;

static gboolean deferred_motion( gpointer data ){
	DeferredMotionDelta* self = reinterpret_cast<DeferredMotionDelta*>( data );
	self->m_function(
		self->m_delta_x,
		self->m_delta_y,
		self->m_state,
		self->m_data
		);
	self->m_motion_handler = 0;
	self->m_delta_x = 0;
	self->m_delta_y = 0;
	return FALSE;
}
public:
DeferredMotionDelta( MotionDeltaFunction function, void* data ) : m_delta_x( 0 ), m_delta_y( 0 ), m_motion_handler( 0 ), m_function( function ), m_data( data ){
}
void flush(){
	if ( m_motion_handler != 0 ) {
		g_source_remove( m_motion_handler );
		deferred_motion( this );
	}
}
void motion_delta( int x, int y, unsigned int state ){
	m_delta_x += x;
	m_delta_y += y;
	m_state = state;
	if ( m_motion_handler == 0 ) {
		m_motion_handler = g_idle_add( deferred_motion, this );
	}
}
};

class FreezePointer
{
unsigned int handle_motion;
int recorded_x, recorded_y, last_x, last_y, center_x, center_y;
GtkWindow* m_window;
GtkWidget* m_widget;
typedef void ( *MotionDeltaFunction )( int x, int y, unsigned int state, void* data );
MotionDeltaFunction m_function;
void* m_data;
public:
FreezePointer() : handle_motion( 0 ), m_function( 0 ), m_data( 0 ){
}
static gboolean motion_delta( GtkWidget *widget, GdkEventMotion *event, FreezePointer* self ){
	int current_x, current_y;
	Sys_GetCursorPos( GTK_WINDOW( widget ), &current_x, &current_y );
#define FIX_LINUX_TOUCHPAD 0 /* issues with this: mouse juddering
													in win10 (system is already at normal scaling)
													Leaving the DPI scaling to the application instead of the system half fixes it
													in GNU/Linux
													Mouselook is broken with custom Input Coordinate Tranformation */
#if FIX_LINUX_TOUCHPAD
	const int dx = current_x - self->last_x;
	const int dy = current_y - self->last_y;
	const int ddx = current_x - self->center_x;
	const int ddy = current_y - self->center_y;
	self->last_x = current_x;
	self->last_y = current_y;
	if ( dx != 0 || dy != 0 ) {
		//globalOutputStream() << "motion x: " << dx << ", y: " << dy << "\n";
		if ( ddx < -32 || ddx > 32 || ddy < -32 || ddy > 32 ) {
			Sys_SetCursorPos( GTK_WINDOW( widget ), self->center_x, self->center_y );
			self->last_x = self->center_x;
			self->last_y = self->center_y;
		}
#else
	const int dx = current_x - self->center_x;
	const int dy = current_y - self->center_y;
	if ( dx != 0 || dy != 0 ) {
		//globalOutputStream() << "motion x: " << dx << ", y: " << dy << "\n";
		Sys_SetCursorPos( GTK_WINDOW( widget ), self->center_x, self->center_y );
#endif
		self->m_function( dx, dy, event->state, self->m_data );
	}
	return FALSE;
}

void freeze_pointer( GtkWindow* window, GtkWidget* widget, MotionDeltaFunction function, void* data ){
	ASSERT_MESSAGE( m_function == 0, "can't freeze pointer: already frozen" );

	const GdkEventMask mask = static_cast<GdkEventMask>( GDK_POINTER_MOTION_MASK
														 | GDK_POINTER_MOTION_HINT_MASK
														 | GDK_BUTTON_MOTION_MASK
														 | GDK_BUTTON1_MOTION_MASK
														 | GDK_BUTTON2_MOTION_MASK
														 | GDK_BUTTON3_MOTION_MASK
														 | GDK_BUTTON_PRESS_MASK
														 | GDK_BUTTON_RELEASE_MASK
														 | GDK_VISIBILITY_NOTIFY_MASK );

	GdkCursor* cursor = gdk_cursor_new( GDK_BLANK_CURSOR );
	//GdkCursor* cursor = create_blank_cursor();
	//GdkGrabStatus status =
	/* fixes cursor runaways during srsly quick drags in camera
	drags with pressed buttons have no problem at all w/o this */
	gdk_pointer_grab( GTK_WIDGET( window )->window, TRUE, mask, 0, cursor, GDK_CURRENT_TIME );
	//gdk_window_set_cursor ( GTK_WIDGET( window )->window, cursor );
	/* is needed to fix activating neighbor widgets, that happens, if using upper one */
	gtk_grab_add( widget );

	gdk_cursor_unref( cursor );

	Sys_GetCursorPos( window, &recorded_x, &recorded_y );

	/* using center for tracking for max safety */
	gdk_window_get_origin( widget->window, &center_x, &center_y );
	center_y += widget->allocation.height / 2;
	center_x += widget->allocation.width / 2;

	Sys_SetCursorPos( window, center_x, center_y );

	last_x = center_x;
	last_y = center_y;

	m_widget = widget;
	m_window = window;

	m_function = function;
	m_data = data;

	handle_motion = g_signal_connect( G_OBJECT( window ), "motion_notify_event", G_CALLBACK( motion_delta ), this );
}

void unfreeze_pointer( bool centerize ){
	ASSERT_MESSAGE( m_function != 0, "can't unfreeze pointer: is not frozen" );

	g_signal_handler_disconnect( G_OBJECT( m_window ), handle_motion );

	m_function = 0;
	m_data = 0;

	if( centerize ){
		Sys_SetCursorPos( m_window, center_x, center_y );
	}
	else{
		Sys_SetCursorPos( m_window, recorded_x, recorded_y );
	}
//	gdk_window_set_cursor( GTK_WIDGET( m_window )->window, 0 );
	gdk_pointer_ungrab( GDK_CURRENT_TIME );

	gtk_grab_remove( m_widget );
}
};





class DeferredAdjustment
{
gdouble m_value;
guint m_handler;
typedef void ( *ValueChangedFunction )( void* data, gdouble value );
ValueChangedFunction m_function;
void* m_data;

static gboolean deferred_value_changed( gpointer data ){
	DeferredAdjustment* self = reinterpret_cast<DeferredAdjustment*>( data );
	self->m_function(
		self->m_data,
		self->m_value
		);
	self->m_handler = 0;
	self->m_value = 0;
	return FALSE;
}
public:
DeferredAdjustment( ValueChangedFunction function, void* data ) : m_value( 0 ), m_handler( 0 ), m_function( function ), m_data( data ){
}
void flush(){
	if ( m_handler != 0 ) {
		g_source_remove( m_handler );
		deferred_value_changed( this );
	}
}
void value_changed( gdouble value ){
	m_value = value;
	if ( m_handler == 0 ) {
		m_handler = g_idle_add( deferred_value_changed, this );
	}
}
static void adjustment_value_changed( GtkAdjustment *adjustment, DeferredAdjustment* self ){
	self->value_changed( adjustment->value );
}
};


#endif